Catches Of Species Research Articles

Drifting fish aggregating devices in the Indian ocean impacts, management, and policy implications

The Indian Ocean has seen a rise in technologically advanced drifting fish aggregating devices (dFADs), significantly increasing tropical tuna catches. These devices, equipped with GPS buoys and echo sounders, enhance fishing efficiency but also lead to increased juvenile tuna and bycatch species catches, ghost fishing, and abandoned gear. This study assesses the technological sophistication, and ecological impacts of dFADs in the region, particularly their role in IUU fishing when they drift into the Somali EEZ. Over a six-month period, 80-dFADs were opportunistically recovered along the four-sample coastline, with 63 being included analysis. None of the recovered dFADs complied with IOTC regulations. The study estimated the potential number of dFADs per km per annum over the Somali shelf as 1395 dFADs that could theoretically be recovered annually. This underscores substantial regulatory non-compliance and emphasizes the need for enhanced monitoring, stricter regulations, and IOTC cooperation to address the ecological and economic impacts on regional marine ecosystems and communities.

Questionnaire surveys to investigate marine mammal fisheries bycatch: systematic review and best practice

Bycatch is the most significant threat to marine mammals globally. There are increasing requirements for national governments to fulfil their obligations to international agreements and treaties to assess fisheries catch and bycatch of non-target species. Questionnaire surveys represent one low-cost method to collect data to estimate fisheries catch and bycatch of vulnerable species including marine mammals. Questionnaire surveys can be particularly advantageous when bycatch is being investigated on large spatial and temporal scales, or in data-poor areas. This review aims to provide the necessary guidance required to design and conduct questionnaire studies investigating marine mammal bycatch. To do so, a systematic review was conducted of the methods used in 91 peer-reviewed or grey literature questionnaire studies from 1990 to 2023 investigating marine mammal bycatch. Literature was searched, screened, and analysed following the RepOrting standards for Systematic Evidence Syntheses (ROSES) protocols. A narrative synthesis and critical evaluation of the methods used were conducted and best practice recommendations are proposed. The recommendations include suggestions for how to generate representative samples, the steps that should be followed when designing a questionnaire instrument, how to collect reliable data, how to reduce under-reporting and interviewer bias, and how weighting or model-based bycatch estimation techniques can be used to reduce sampling bias. The review’s guidance and best practice recommendations provide much-needed resources to develop and employ questionnaire studies that produce robust bycatch estimates for marine mammal populations where they are currently missing. Recommendations can be used by scientists and decision-makers across the globe. Whilst the focus of this review is on using questionnaires to investigate marine mammal bycatch, the information and recommendations will also be useful for those investigating bycatch of any other non-target species.

The potential impacts of exploitation on the ecological roles of fish species targeted by fisheries: A multifunctional perspective.

Examining ecosystem functioning through the lens of trait diversity serves as a valuable proxy. It offers crucial insights into how exploitation affects the specific ecological roles played by fisheries targeted species. The present study investigates the potential impacts of exploitation on the ecological roles of fish species targeted by fisheries through an examination of trait diversity. It focuses on the trait diversity of fish landed by local and coastal fleets in the Azores archipelago over the past four decades. Fourteen functional traits were merged to data on fish assemblages landed by both fishing fleets from 1980 to 2020. These traits corresponded to four fundamental fish functions: habitat use, locomotion, feeding and life history. Variability in functional diversity metrics (i.e., functional richness- FRic, functional evenness- FEve, functional divergence-FDiv, and functional dispersion- FDis) among fleets, functions and across decades was assessed using null models. The results revealed similar trait diversity between assemblages landed by local and coastal fishing fleets with overall trait diversity remaining relatively stable over time. However, fishery activities targeted a wide range of functional traits. Additionally, seasonal availability and increased catches of certain fish species can significantly alter trait diversity and their associated functions. The findings highlight the importance of addressing fishing impacts on species traits and their ecological roles, which is crucial for long-term fisheries and ecological sustainability.

Assessing microplastic abundances in freshwater fishes in a subtropical African reservoir

Microplastics are emerging pollutants of global concern, and their presence in the aquatic environment poses a serious risk for aquatic biota. While many studies have been conducted on the presence of microplastics in marine habitats, little research has been done in freshwater African reservoirs on microplastic pollution and their impacts on fish within the subtropical regions. To bridge this gap, the current study investigated microplastic abundances and distribution in freshwater fish within Nandoni reservoir, South Africa, across two seasons (i.e., hot–wet, cool–dry). Fish were randomly sampled using seine and gill nets from seven sites within the reservoir. In the laboratory, fish were then sorted according to taxa before dissecting them to remove the gills and the gastrointestinal tract (GIT). The organs were digested using hot hydrochloric acid and hydrogen peroxide, and the microplastics were classified according to their colours and shapes. Among the 94 fishes (i.e., 8 species) examined, microplastics were detected in 86.6% of the eight species caught. Microplastics were dominant in the gills and GIT during the cool–dry and hot–wet seasons, respectively. High microplastic abundances were found in the gills of Micropterus salmoides and the GIT of Coptodon rendalli, where fibres and the transparent colour were the most dominant. The results further showed high microplastic abundances in benthopelagic feeders highlighting that habitat influences fish consumption of microplastics whether directly or indirectly. Significant differences were observed in the feeding zone and season for all microplastic types. Microplastic sources in the reservoirs could be due to anthropogenic activities such as illegal dumping, fishing, and agriculture. Thus, there is a need for further investigation into the relation of fish weight, fish sex and body in relation to microplastic pollution. The highlighted ecological factors should be taken into consideration for future research and management actions aimed at mitigating and protecting the negative impacts of microplastic pollution on environmental and human health.

Evidence to inform spatiotemporal management of a western Pacific Ocean tuna purse seine fishery.

Fisheries can profoundly impact co-occurring species exposed to incidental capture. Spatiotemporal fisheries management holds substantial potential to balance socioeconomic benefits with ecological costs to threatened bycatch species. This study estimated the effect of the spatial and temporal distribution of effort by a western Pacific Ocean tuna purse seine fishery on catch rates of target and at-risk species by fitting spatially explicit generalized additive multilevel regression models within a Bayesian inference framework to observer data. Mean field prediction surfaces defined catch rate hotspots for tunas, silky sharks, rays, and whale sharks, informing the design of candidate area-based management strategies. Due to limited sample sizes, odontocete and marine turtle catch rate geospatial patterns were summarized using simple 2D hexagonal binning. Effort could be focused in two areas within core fishing grounds to reduce overlap with hotspots for silky sharks, rays, and whale sharks without affecting target catch. Effort could be shifted outside of core fishing areas to zones with higher target tuna catch rates to reduce overlap with hotspots for at-risk species. Sparse and small marine turtle and whale shark hotspots occurred across the fishing grounds. Results did not identify opportunities for temporally dynamic spatial management to balance target and at-risk catch rates. Research on the economic and operational viability of alternative spatial management strategies is a priority. A small subset of sets had disproportionately large odontocete captures. Real-time fleet communication, move-on rules, and avoiding sets on dolphin schools might reduce odontocete catch rates. Managing set association type and mesh size present additional opportunities to balance catch rates of at-risk and target species. Employing output controls that effectively constrain the fishery would alter the spatial management strategy to focus fishing within zones with the lowest ratio of at-risk bycatch to target tuna catch. Findings inform the design of alternative spatial management strategies to avoid catch rate hotspots of at-risk species without compromising the catch of principal market species.

From rarity to reality: the hidden abundance of critically endangered deep-sea little gulper shark (Centrophorus uyato) in the southern Adriatic Sea

The little gulper shark, Centrophorus uyato (Rafinesque, 1810), is a critically endangered and poorly known deep-sea shark that is considered very rare in certain parts of the Mediterranean, particularly the Adriatic Sea. Between June and August 2023, a total of 47 individuals (25 females and 22 males) were documented 3 to 4.5 NM off Grama Bay in Vlorë, Albania, at depths ranging from 400 to 450 meters. All the recorded individuals were adults, measuring in average 90.53 cm total length and weighting 4.26 kg. Detailed examinations were performed on 10 individuals (5 males and 5 females), while the remaining specimens were retained by fishermen and subsequently sold for consumption. Local ecological knowledge revealed a consistent presence of the species in the longline catches in the studied area. The findings presented in the current manuscript indicate that the species may be more common in the southernmost Adriatic Sea than previously thought. Moreover, data herein support the postulation that the species prefer submarine canyons within the upper slopes.

Atlantis end-to-end modeling to explore ecosystem dynamics in the Strait of Sicily, Central Mediterranean Sea

This paper describes the first application of the end-to-end model Atlantis in the Strait of Sicily (SoS). The model is designed to simulate ecosystem dynamics under the influence of fishing activities. Model performance was evaluated by comparing predicted biomass and catch of target species against observed data, utilizing multiple quantitative metrics. It reproduces accurately trophic dynamics, and biomass and catch of main target species in the SoS. Sensitivity analysis of the key model parameters identified nutrient loading and fishing pressure as the major processes influencing the ecosystem trophic spectrum and generating bottom-up and top-down effects. The results also emphasized the importance of incorporating uncertainty estimation in model predictions and robust selection of key parameters. The SoS Atlantis represents a strategic tool for the application of Ecosystem Approach to Fisheries Management (EAFM) in the Strait of Sicily and for assessing the effect of alternative management scenarios under a holistic framework.

The Origin of the Chionoecetes Opilio Snow Crab Larvae in the Kara Sea

Most likely, the non-indigenous snow crab opilio, Chionoecetes opilio, entered the Kara Sea from the Barents Sea, both due to the migration of adults and with currents at the larval stage. At the moment, all bottom stages, including mature individuals and a large number of pelagic larvae are present in the Kara Sea. However, the origin of the larvae has not yet been clarified. The larvae that hatched in the Kara Sea should be at an earlier stage of development compared to the Barents Sea larvae that got here due, to later development of phytoplankton and, accordingly, later hatching. The larvae of the snow crab Chionoecetes opilio and the spider crab H. araneus were collected in the central and southwestern parts of the Kara Sea in July — early August 2019 by the Bongo zooplankton net 60 cm in diameter. It was established that the larvae were unevenly distributed across the Kara Sea. The main concentrations were found on the border with the Barents Sea in the St. Anna Trough (up to 860 ind./m2), and relatively high concentrations of larvae were noted in the southwestern part, where their abundance at the stations varied from 18 to 302 ind./m2. In the zone of the Ob-Yenisei plume, crab larvae were absent or their abundance was minimal. Using molecular genetic methods, the species identity of 361 larvae (344 C. opilio and 17 H. araneus) was reliably determined, and measurements of a number of morphological structures were made for 401 larvae. Significant differences in size at the zoea stage II between C. opilio and H. araneus were established. In most of the Kara Sea in July 2019, in zooplankton samples, crab larvae were represented by zoea I C. opilio with rare specimens of zoea I H. araneus of the Kara Sea origin. Only in the southwestern part, on the border with the Barents Sea, the presence of zoea II C. opilio and H. araneus was observed in samples with an increase in the proportion of the latter species in catches, which probably originate from the Barents Sea.

Large pelagic fish exploitation by longliners in the Atlantic Ocean and Mediterranean Sea: A contribution to spatial planning and sustainable fisheries

Understanding longline fisheries dynamics is crucial for sustainable resource management. This study aims to provide a panorama of the fishing effort of the principal nations that have exploited tuna and associated species in the Atlantic Ocean for the past decade, integrating vessel data from Global Fishing Watch (GFW) and catch data from the International Commission for the Conservation of Atlantic Tunas (ICAAT), with specific information on the production of these different fleets and resources. Twelve nations represented 94.6 % of all Apparent fishing hours (AFH) of the total effort in the Atlantic Ocean and 99.9 % of all catches in the last years. Our study revealed that regions proximate to the continental shelf break and oceanic islands exhibit notably higher fishing effort than other areas within the Atlantic Ocean. We also highlight a declining trend in fishing efforts in the last ten years, likely due to regulation and overfishing. The blue shark (Prionace glauca) was the most caught species in biomass, representing 38.1 %; bigeye tuna (Thunnus obesus) represented 20.5 %; swordfish (Xiphias gladius) 15.1 %; albacore tuna (Thunnus alalunga) 11.3 %, and yellowfin tuna (Thunnus albacares) 6.1 %. The alarming trends in pelagic shark catch emphasise the need for immediate conservation actions. Management strategies should target critical nations, addressing their significant contributions to shark catch. The lack of information on several species and periods highlights the need for comprehensive research and management initiatives.

Is my fishing gear impacting the habitat? An impact assessment in four fisheries in the Northwest Mexican Pacific

The impacts of fishing activities on habitats for commercially important species may, directly and indirectly, influence species and associated communities. These effects include those on target species, bycatch species, habitats, etc. In this study, the impact of small-scale fisheries on habitats was evaluated in four fishing communities from the Northwest Mexican Pacific. The species and size selectivity of several fishing gear were evaluated, and the spatial distribution of catches was studied to assess the impacts of fishing gear using a Consequence Spatial Analysis (CSA). Our results showed that in finfish fisheries from Guaymas and Isla Natividad, the catch of the target species represents more than 75% of the total catch and in El Rosario, the catch represents less than 50%. We assessed 42 habitat types in four communities, which were qualified with low-risk scores. The fishing gears used to target commercial species are selective to optimal sizes above their maturity size. The results contribute to improving management in data-poor fisheries by evaluating the impacts of fishing on habitats and discussing their relevance for implementation.

Addressing offshore wind farms compatibilities and conflicts with marine conservation through the application of modelled benchmarking scenarios

Offshore wind power generation structures are scheduled for development in the Canary Islands, potentially resulting in spatial overlap with various maritime activities, particularly fishing. It is crucial to point out that some areas that are considered suitable for installing these structures are in protected zones that are part of the Natura 2000 network, and do not have any prior environmental impact assessments. The research delved into the efficacy of utilizing Ecopath with Ecosim software to examine the consequences of implementing this technology in the study area, employing an ecosystem-based approach. To address this question, simulations were executed by assessing three distinct scenarios. The results suggest that there would be changes in the distribution of keystone species such as top predators, alongside a conspicuous decline in the abundance and catches of target species of the fishery. The Ecospace model holds the potential to forecast the impacts of offshore wind installations; however, crucial factors must be carefully considered, such as the lack of information. Notwithstanding the constraints, research like this demonstrates the efficacy of spatial ecosystem modelling in exploring this issue.

Performance indicators of the red grouper (Epinephelus morio) fishery along the Yucatan coast, Southeast Mexico

This study assesses the Fishery Performance Indicators (FPI) of the red grouper fishery, currently overexploited, aiming to identify factors for sustainable management and economic growth. Evaluation spans commercial and recreational fishing activities and encompasses output indicators focusing on ecology, economy, and community, through 68 metrics, including measures related to stock abundance, ecosystem impacts (e.g., habitat degradation, bycatch rates), and social aspects (e.g., community participation in management). Input indicators assess enabling conditions such as diseases, water quality, air pollution, biodiversity, etc. Scoring involved reviewing fishery data and information from various sources including scientific literature, technical reports from workshops and meetings, journalistic notes, databases, and unpublished data; with each metric scored according to its specific system. The red grouper fishery exhibits strengths in harvest and community involvement but grapples with stock and ecological concerns. Medium-size fleet perform adequately, yet challenges arise from aging vessels and market fluctuations. Artisanal fleet encounter issues like illegal fishing and economic struggles, while recreational fishing faces stock and ecological worries. Persistent environmental and governance challenges underscore deficiencies in management practices and fishing markets. Enhancing the red grouper fishery requires fair pricing, effective stock management, and sustainability efforts in co-management, fisheries management, and post-harvest processes. Improving gear selectivity is crucial for effective stock management, involving minimizing catches of juvenile red grouper and incidental species. Insufficient bargaining power results in an unfair market and disadvantages for fishermen, leading to losses. To address these issues, it is essential to diversify market channels, stabilize prices, and advocate for fair pricing mechanisms. Empowering fishermen through collective bargaining and regulating credit agreements can ensure fairness. Additionally, policy interventions are necessary to support fishermen and foster a more equitable industry.

Analysis of changes in biological parameters and stocks of coho salmon <i>Oncorhynchus kisutch in</i> the Bolshaya River (western Kamchatka) in 1941–2023

Changes in the spawning part of the Bolshaya River population of coho salmon are considered for 1941–2023. Long-term trends are revealed for the most important biological parameters of adults, in particular, decreasing in size, weight (except of late-race females), and fecundity of returning fish. The parameters for different races and sexes in different periods of time are compared statistically, with frequency analysis. Influence of duration of freshwater and marine feeding on size, weight and fecundity of coho salmon is estimated. The portion of this species in salmon catches in the Bolshaya River basin was 19 %, on average, in 1941–2023, the second after pink salmon. In 2007–2023, the catch and reproduction rate of coho salmon exceeded the average values for 1972–2002 by an order, though their registered escapement to the river decreased in 3 times. Obviously, the spawning runs were underestimated. Increasing the funding of aerial surveys on coho salmon is proposed, to make them longer and more extended and detailed. Besides, the passing of salmon to the spawning grounds can be modeled on the data of reproduction multiplicity.

Potential of Sea Urchin Mesocentrotus nudus as a Target Catch Species in the Pacific Ocean off Eastern Hokkaido, Japan.

Scientific reports on the distribution of Mesocentrotus nudus in Hokkaido are limited from Cape Soya to Cape Erimo along the coast of the Sea of Japan; however, fishery statistics show that its distribution has extended to the Sea of Okhotsk and Pacific Ocean off Hokkaido. In 2021, large-scale harmful algal blooms (HABs) occurred in the Pacific Ocean off eastern Hokkaido, resulting in the massive die-off of marine organisms, including M. nudus. This study aimed to redefine the distribution of M. nudus in the Pacific Ocean off eastern Hokkaido after the HABs. Field surveys were conducted in July, August, and December 2023 in Akkeshi, the site farthest from Cape Soya among the areas where irregular catches of M. nudus have been recorded in eastern Hokkaido, and the distribution of this species was confirmed in August and December. All sea urchins collected were >6 years of age, indicating that they survived the HABs. High gonad indices and spermatozoa-filled gonads were observed in the sea urchins collected in December, suggesting that the reproductive cycle of M. nudus in Akkeshi may be close to that observed in specimens off Wakkanai, Cape Soya. Warming trends may cause population increases in the future.

The Problems of DNA-Barcoding the Shads of Genus Alosa (Alosidae) of the Ponto-Caspian Basin

—Numerous studies show that species identification of representatives of the genus Alosa using various genetic markers is often difficult and the search for more specific biomarkers is required. For the first time we analyzed polymorphism of COI gene fragment of mitochondrial DNA of two representatives of this genus (A. tanaica and A. kessleri), supplemented with new data on A. immaculata, from the waters of the Ponto-Caspian basin in comparative aspect with other representatives of the herring (Clupeoidea) genera Alosa, Clupea, Clupeonella, Sprattus, and Sardinops. The main result was the conclusion that within the genus Alosa, it is not possible to identify species using the marker used. On the one hand, specimens collected from morphologically distinct individuals and identified as different species have the same haplotypes. On the other hand, samples belonging to different species differ from each other by an insignificant number of nucleotide substitutions and do not form independent clades on the phylogram and haplotype network. This indicates the absence of genetic differentiation between the studied samples of herrings of genus Alosa into separate species and species groups when using DNA barcoding based on the COI gene. The reasons for such a phenomenon may be the following: (1) incorrect identification of species in catches, since shads (Alosidae) have high morphological flexibility and in many species, the main external morphological characters often overlap; (2) recent time of speciation by the standards of biological evolution for shads of genus Alosa; (3) difference in proportion of interspecific hybrids, which can vary significantly between populations of the same species.

Non-native fish species in the North Aegean Sea: a review of their distributions integrating unpublished fisheries data

Fisheries-dependent data and information gathered through fisheries-related scientific surveys can significantly contribute to research on the patterns and processes underlying marine biological invasions and their interactions with fisheries. This study presents an overview of the presence of non-native fish species in the North Aegean Sea, offering insights into their distributions and impact on fisheries. The findings are based on a comprehensive compilation of commercial fisheries-dependent and scientific survey data collected in Greece from 2016 to 2023, along with a systematic review of the international scientific literature. The study resulted in the documentation of the presence of 37 non-native fish species, including several recorded for the first time in the area. The results suggest that non-native fish species invasions in the North Aegean Sea are dynamic. Although most species were classified as casual, and the frequencies of occurrence as well as the quantities in commercial fisheries catches of established species are smaller than in the South Aegean Sea, species introductions and the extent of occurrence and area of occupancy of several species have been increasing since the 2000s. The significance of non-native fish species is becoming increasingly relevant to commercial fisheries in the study area. This is particularly evident in the Northeastern Aegean Sea, where catches of non-native species are on the rise, and new species with potential commercial value have emerged in recent years.

WITHDRAWN: Movements of blue shark (Prionace glauca) inferred from oceanographic conditions in the northeastern Pacific using conventional tagging.

Given that blue shark (Prionace glauca) is the most caught species in Northeast Pacific by the Mexican fleet in target and bycatch fisheries, it is essential to understand its movement behavior under mesoscale oceanographic conditions to maintain a sustainable fishery. Through the initiative of the conventional shark tagging program in the artisanal fleet for research purposes in the region, this program is being expanded to cover a larger area in the Northeast Pacific Ocean through the support of the industrial fleet. Therefore, the objective of the present study is to verify the differences in size and sex of conventionally tagged blue sharks with respect to the type of hooks where they were caught. The horizontal distribution and effect of environmental-oceanographic variables on the yield of conventional tagging using the generalized additive model (GAM) were also examined. In the 2010-2018 period, 870 blue sharks were tagged by the artisanal and industrial fleets, of which 8.4% were recovered, showing that the size of the sharks is conditioned to the fishing area of each fleet, but not to the type of hook used. Their movements reflected a horizontal distribution with no fixed course but preferring temperate anomaly waters, mainly near cyclonic eddies. Assessing that the best tagging yield was proportional to the abundance, the GAM confirmed that the explanatory variables (Lat-Long, Year, Curl, Lunar Index, SSTa and Douglas sea scale) have explained 41.9% of the total deviance, whereof spatial interaction with both fleets was the main predictor followed by Year which was influenced by climatic events.

Kaupallinen kalastus Inarijärvellä – kestävää sopeutumista muuttuvaan toimintaympäristöön?

The operational environment of commercial fishing in the North is changing due to climate change and other environmental and socio-economic drivers. In this study, we combine the practitioner knowledge of commercial fishers operating on the subarctic Lake Inari in northern Finland with long-term meteorological and hydrological observations from the region. Our interviews show that fishers have adopted various short-term strategies to cope with difficult weather conditions, among them flexibility in timing and location of fishing, as well as in catch species and gear. The livelihood is diversified both within and outside fishing to enhance the profitability. Responses of fishers to future uncertainties were varied and based on individual rather than community behavior. Four distinct longer-term adaptation strategies utilized by fishers differ in terms of the catch species, investments, and risk levels. Finally, we discuss the sustainability of the identified adaptation strategies, and the governance aspects of the livelihood.

Comparative Study on Current Fishing Status of Paalameenmadu and Kallar Barmouths in Batticaloa District,

Batticaloa lagoon is one of the productive estuaries on the East coast of Sri Lanka and is connected to the sea at two points, Paalameenmadu and Kallar barmouths. The entire dynamics of the lagoon is based on the seasonal opening and closing of the above barmouths which influences the fish catch composition in nearby fishing areas. This study collects information on current fishing practices, species composition of the catch, and seasonal catch species composition, the level of awareness on fishing regulation and sustainable fishery using semi-structured questionnaire. Fisheries data were collected from 10 major barmouth fishery landing sites from January to April 2021. 210 respondents were selected using a stratified random sampling technique. A semi-structured questionnaire was used to collect responses after a pre-test and analysed with descriptive statistics method using SPSS. The study revealed that Paalameenmadu barmouth was opened annually and Kallar barmouth has been closed for the last five years. The most practiced crafts in Paalameenmadu are outboard Fiber Reinforced Plastic boats (OFRP) by 35.26% of fishers and small lagoon canoes by 87.04% fishers in Kallar. A total of seven types of fishing gears are used, among them hook and line, cast net, and dragnet were identified as major fishing gears operated. 30 aquatic species have been recorded in the catch, representing 17 families. Among them, dominant fish families are Scombridae 17.11% and Penaeidae 14.81% in Paalameenmadu. In the Kallar, family Penaeidae 18.75% and Gerreidae 16.32% have been recorded. Barmouth opening is favourable for fishing and 38.57% Penaeidae species were caught during barmouth opening period. Community response that Irregular and early barmouth opening have caused a reduction in fish production which impacts on economic activities. Fishermen have good awareness on importance of fishery resources sustainability and these resources need to be preserved for future generations through proper management practices.

The impact of ocean warming on selected commercial fisheries in New Zealand

AbstractWarming oceans affect the growth, reproduction and location of fish species. Using a bioeconomic framework, we estimate the relationship between sea surface temperature (SST) and the catch of de facto open‐access commercial fisheries of flatfish, trevally and jack mackerel in New Zealand. Assuming either a logarithmic or quadratic relationship between the SST and the carrying capacity of the fish stock, we consider three fishing methods (bottom trawl, set net and midwater trawl) and two measures of effort (count and duration). We show that ocean warming results in an increase in catch for all species if we assume a logarithmic relationship, with the highest marginal product of SST () for jack mackerel caught using midwater trawl. The highest marginal revenue product (computed by the MPSST, current price and fished area) is found for flatfish caught by set net. However, when assuming a quadratic relationship, there is a threshold above which catch starts to decrease, with the maximum catch of species ranging between 10 and 12.2°C. These results also vary spatially, with higher values of MPSST observed in areas closer to the South Pole. Our findings are relevant for any review of fisheries management systems in response to ocean warming.